<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <title>Document</title>
    </head>
    <body>
        <script>
            const length = 10;
            const fn = function () {
                console.log(this);
                console.log(this.length);
                return this.length + 1;
            };
            const obj = {
                length: 5,
                test: function () {
                    return fn();
                },
            };
            //下面输出是什么？
            console.log(obj.test());
        </script>
    </body>
</html>
